棉花GhLTPG6基因的克隆、表达模式及功能初步分析

Cloning,Expression Pattern and Function Analysis of GhLTPG6 Gene in Gossypium hirsutum

脂质是生物膜的主要组成成分,它参与植物碳源储存、抵抗病原菌侵袭等多种生理过程。植物中脂质转运蛋白(glycosylphosphatidylinositol-anchored lipid transfer protein,LTPG)参与植物体内蜡质的运输,在调控植物生长发育过程发挥重要作用。本研究从陆地棉TM-1中克隆了1个脂质转运蛋白基因GhLTPG6(GH_D05G0009),分析了GhLTPG6在不同组织器官及低温、高温、高盐和干旱胁迫下的转录响应。序列分析表明GhLTPG6的c DNA全长645 bp,并分析GhLTPG6基因的理化性质及其功能结构域,其包含1个LTPG结构域(AAI)。系统进化树分析表明GhLTPG6与AtLTPG6在同一进化分枝上,亲缘关系最近。亚细胞定位结果显示GhLTPG6定位于质膜上。RT-qPCR分析表明GhLTPG6在10DPA的纤维中表达量最高,GhLTPG6异源过表达拟南芥发现,GhLTPG6对拟南芥莲座叶表皮毛的长度有促进作用,而对其密度无显著影响,说明GhLTPG6可能对棉花的伸长起重要作用。低温处理后,GhLTPG6的表达量随着时间推移逐渐降低,而在高温、高盐和干旱处理后,GhLTPG6的表达量逐渐上升,说明GhLTPG6同时参与棉花的抗逆胁迫。以上研究结果表明GhLTPG6基因可能在棉花伸长期起重要作用,且可能参与棉花的非生物胁迫响应,该基因功能具有潜在的多效性。

Lipids are the main components of biofilms,which participate in a variety of physiological processes such as plant carbon source storage,resistance to pathogens and so on.Glycosylphosphatidylinositol-anchored lipid transfer protein(LTPG)in plants is involved in the transport of wax in plants and plays an important role in regulating the growth and development of plants.In this study,a lipid transfer protein gene GhLTPG6(GH_D05G0009)was cloned from upland cotton TM-1,and the transcriptional response of GhLTPG6 to different tissues and organs and under low temperature,high temperature,high salt and drought stress was analyzed.Sequence analysis showed that the cDNA of GhLTPG6 was full-length 645 bp.We analyzed the physicochemical properties and functional domain of GhLTPG6,which contained a LTPG domain(AAI).Phylogenetic tree analysis showed that GhLTPG6 and AtLTPG6 were closely related to each other in the same evolutionary branch.The results of subcellular localization showed that GhLTPG6 was located on the plasma membrane.RT-qPCR analysis showed that the expression of GhLTPG6 was the highest in the 10DPA of the fiber development.Heterologous overexpression of GhLTPG6 in Arabidopsis found that GhLTPG6 could promote the length of epidermal hair of Arabidopsis rosette leaves,but had no significant effect on its density,indicating that GhLTPG6 may play an important role in the fiber elongation stage.After low temperature treatment,the expression of GhLTPG6 decreased gradually with the passage of time,while after high temperature,high salt and drought treatment,the expression of GhLTPG6 increased gradually,indicating that GhLTPG6 was also involved in the stress resistance of cotton.The above results show that GhLTPG6 gene plays an important role in the elongation stage of cotton and may be involved in abiotic stress response of cotton,so the function of GhLTPG6 has potential multiplicity.